The EUV imager (EUI) is a key instrument on board the Solar Orbiter mission. It will provide critical context images with the Full Sun Imager (FSI) which will show the location of coronal holes, active regions, filaments, flares and propagations of large-scale waves. The High Resolution Imagers (HRI) will be able to observe in sub-second time cadence and 100 km spatial resolution at perihelion in the solar atmosphere allowing us to search for small scale physical phenomena that create outflowing plasma from the Sun. This talk will summarise the functionality of the instrument and how the data will contribute to the science goals of the Solar Orbiter mission.